How Gas Turbine Engines Work

Advantages and Disadvantages of Jet Engines

So wh­y does the M-1 tank use a 1,500 horsepower gas turbine engine instead of a diesel engine? It turns out that there are two big advantages of the turbine over the diesel:

Gas turbine engines have a great power-to-weight ratio compared to reciprocating engines. That is, the amount of power you get out of the engine compared to the weight of the engine itself is very good.

Gas turbine engines are smaller than their reciprocating counterparts of the same power.

­The main disadvantage of gas turbines is that, compared to a reciprocating engine of the same size, they are expensive. Because they spin at such high speeds and because of the high operating temperatures, designing and manufacturing gas turbines is a tough problem from both the engineering and materials standpoint. Gas turbines also tend to use more fuel when they are idling, and they prefer a constant rather than a fluctuating load. That makes gas turbines great for things like transcontinental jet aircraft and power plants, but explains why you don't have one under the hood of your car.